Adjustable t-square head for mat cutters and similar devices



May 20, 1958 R. MIDDENTS 2,835,037

ADJUSTABLE T-SQUARE HEAD FOR MAT CUTTERS AND SIMILAR DEVICES Filed June 27, 1956 2 Sheets-Sheet 1 INVENTOR H w l6 -fO/azR./|4Zdd@1zt$ 26 10 ATTORNEY May 20, 1958 J. R. MIDDENTS ADJUSTABLE T-SQUARE HEAD FOR MAT CUTTERS AND SIMILAR DEVICES Filed June 27 1956 2 Sheets-Sheet 2 \J m INVENT OR ATTORNEY ADJUSTABLE T -SQUARE HEAD FOR MAT CUTTERS AND SIMILAR DEVICES John R. Middents, Furth Bayern, Germany Application June 27, 1956, Serial No. 594,332

' Claims (11. 33--76) (Granted under Title 35, U. S. Code (1952), see. 266) The invention described herein, if patented, may be 7 manufactured and used by or for the Government for governmental purposes, without the payment to me of 1 any royalty thereon.

' This invention relates to straight edge cutters and more particularly to cutters of that type designed for cutting mats for use in mounting photographs, engravings, etc.

One of the objects of the invention consists in providing a cutter guide or track in the form of a T square in which the head portion, which would ordinarily be placed against an edge of a drawing board, table top or other surface on which .the mat material is supported, is demountable so that the T square may, when desired, be

(placed fiat on a table top with the shortened head engaging an edge of the cardboard or other backing on which the cutting operation is to take place.

Another object of the invention consists in theprovision of a spring device which serves to frictionally hold the demountable head portion in either its operative or inoperative position.

A furtherv object of the invention resides in providing a reciprocably'mounted cutter comprising a demountable carriage and means for adjustably mounting a cutter blade I therein at anangle so as to provide the customary beveled edge around the opening cut in the mat.

Another object of the invention resides in providing a reciprocably-mounted carriage and inclined cutter blade in which the knob for operating the carriage is positioned in substantially vertical alignment with the point of the Other objects and advantages of the invention will be apparent from the following description when taken in W connection'with the accompanying drawings, in which Figure l is an exploded perspective view of the mat cutter;

Figure 2 is an enlarged fragmentary detail view showing the cutter in side elevation mounted on a table ready for use;

Figure 3 is a transverse sectional view through the cutter mechanism and showing the same mounted on a table;

Figure 4 is a fragmentary longitudinal sectional view through the mechanism;

"the arrows;

"Figure 8 is a transverse sectional view taken :on line =S -8 :of Figure 6 and looking .in the direction of the 1 .j "Figure 9 is a fragmentary detail viewshowing the :head,

as adjusted in Figure 6, in side elevation, and,

hired States Patent 0 Figure 10 is a side elevational view of the head of the T square as shown in plan view in Figure 5.

Referring to the drawings in greater detail and by reference numerals, the numeral 1 indicates the blade of a T square type of mount for guiding the cutter blade as will hereinafter appear. The head of the T-square is composed of a flat bar 2, which is rigidly secured to the blade 1 as indicated by the screws 3, and a detachable blade 4 provided with a cutaway portion 5 having a width corresponding to the width of the blade 1 and a pressed-up portion 6 which is adapted to cooperate with a dual spring as will shortly appear. The pressed-up portion 6 is integrally connected of course with the main body portion of the plate 4 as indicated by flanges 7, and these flanges bound the cutaway portion 5 as indicated by the numeral 8.

Mounted on the upper surface of the blade 1 of the T square is a trackway 9 which extends throughout the length of the blade and has upturned flanges 10 forming a pair of rails for the cutter which is indicated generally by the numeral 11. Mounted along each edge of the upper face of the blade 1 is a series of linear graduations 12 which may be in the form of paper sheets secured to the surface of the blade or may be etched or otherwise formed thereon. The purpose of these graduations of course is to facilitate measuring the cuts to be made by the cutter 11.

This cutter comprises a body portion 13 having legs or downwardly extending side members 14 which provide bearings for a pair of rollers 15 having annular grooves 16 spaced apart a distance corresponding to the spacing of the rails 10 so that the cutter may be guided along the trackway 9. As will be noted the body portion 13 has its longitudinal side walls tapered upwardly and these walls are provided with upwardly inclined slots 17 which are covered by plates 18 secured to the side walls of the carriage by screws 19. Adjustably mounted within one of these slots 17 is a cutter blade 20 which may be secured in adjusted positions longitudinally of the slot 17 by setscrew 21. It will be apparent that by means of this adjustment the cutting point of the blade can be adjusted with respect to the carriage so as to regulate the maximum depth of the cut into the mat material. The carriage may be moved along the trackway 9 by means of a knob 22 which is secured to the forward end of the body 13 of the carriage by means of a bolt 23 threaded upwardly through the body 13 into the knob 22. In this connection it is to be noted that the knob 22 is so positioned as to be substantially in vertical alignment with the cutting point of the cutter it (Figure 2) so that pressure may be applied vertically downwardly onto the cutter.

When the mat cutter is to be used in conjunction with a table top or the like, the plate 4 which forms a part of the two-part head of the T square is placed vertically of the blade 1 as indicated in Figures 2, fl, 6, 8 and 9, and to this end a dual leaf spring 24 having an upturned vertical end 25 is secured to the cross bar 2, or that portion of the blade mounted on the cross bar, by a screw 26, and it is for this reason that the detachable blade 4 is provided with the cut out portion 5 having a width corresponding substantially to the width of the blade 1. In order to bring the vertically extending spring 25 into play as a clamp for the plate 4, the plate is reversed as indicated in Figure 6 so as to bring the upwardly pressed portion 6 into contact with spring 25 while allowing the flanges 8 to pass downwardly into notches 4' formed in the forward edge of the flat bar portion 2 of the head. Thus the leaf spring 25 presses against the upraised portion 6 so as to force the same against the adjacent end of the trackway 9 and its rails so as to firmly hold the plate in vertical position as shown more clearly in Figure 2. Thus a head of substantial vertical dimensions is provided for cooperation with the edge of a table or the like in firmly holding the blade in the desired position with respect to the mat material which is shown at 30 in Figures 2 and 3 as resting on cardboard or the like 31 which is in turn supported upon the table 32.

It sometimes becomes desirable to use the edge of the cardboard support in conjunction with the T square, and it is for this reason that the head of the T square is made in two parts, one of which is removable, namely the plate 4 just referred to. When the T square is used directly against an edge of the cardboard backing which supports the mat material, the plate 4 is withdrawn from the position shown in Figures 2, 5, 6, 8 and 9 and is placed in parallel relationship to the rigid flat bar portion 2 of the head. And, in order to secure the plate 4 in superposed position on the fiat bar 2, the dual spring 24 is provided with a horizontally extending spring portion 25 spaced slightly above the base portion of the head. Vertically extending pins 25" are positioned adjacent each side of the horizontally extending spring so as to engage the forward edge of the raised portion 6 of the plate 4 as the latter is slid into position on the fiat bar 2 with the raised portion under the spring 25 so as to firmly clamp the plate in position until it is to be detached for further use as indicated in Figures 2, 5, 6, 8 and 9.

The operation of the device is believed to have been clearly indicated in connection with the description of the various structural details, however, it may be pointed out that the cutter 20' is so mounted with respect to the carriage 1113 that it provides a bevel cut as is customary in mat cutting. Moreover, it is to be noted that the carriage 11-13 may be removed from the trackway 9, and thus a series of shallow cuts may be made, which is sometimes desirable, by first making one out then lifting the carriage from the track and bringing it forwardly toward the head of the T square and placing it on the track so as to make successive cuts along the same line of the material.

From the foregoing description taken in connection with the accompanying drawings it will be apparent to those skilled in the art that I have devised a rather simple construction of mat cutter which is adapted for use in conjunction with a table top or may be readily converted for use in conjunction directly with the card board base on which the mat material is usually mounted, that the cutting pressure is applied downwardly in the vertical direction substantially in line with the cutter point, that the blade is mounted so as to form the conventional bevel cuts, and that such cuts may be made by degrees by making a series of shallow cuts through repeated removal of the carriage from the track after each of the shallow cuts, thereby avoiding substantial damage to the cardboard backing by reason of making one final deep cut which would be necessary but for the fact that the carriage can be removed from the track and the previous cut deepened by again applying the cutter to the trackway and drawing it therealong.

in accordance with the patent statutes I have described what I now consider to be the preferred form of the construction, but inasmuch as various minor structural details may be varied without departing from the spirit of the invention, it is intended that all such variations be included within the scope of the appended claims.

I claim:

1. A T-square for mat cutters comprising a blade portion, a trackway mounted thereon, and a two-piece head portion comprising a flat bar rigidly secured to an end of the blade portion and having its inner edge terminating in substantially the vertical plane of the adjacent end of the trackway, and a detachable plate having a cut-out portion intermediate its ends of suflicient dimensions to permit the plate to straddle the blade, a leaf spring secured to the flat bar and located adjacent the proximate end of the trackway, said plate being clamped between the leaf spring and the proximate end of the trackway.

2. A T-square for mat cutters comprising a blade portion, a trackway mounted thereon, and a two-piece head portion comprising a flat bar rigidly secured to an end of the blade portion and having its inner edge terminating in substantially the vertical plane of the adjacentend of the trackway, and a detachable plate having a cut-out portion intermediate its ends of sufiicient dimensions to permit the plate to straddle the blade, a leaf spring secured to the flat bar and located adjacent the proximate end of the trackway and extending vertically of the plane of the bar, and a second spring attached to the bar and having a portion spaced slightly therefrom, said plate being clamped between the vertically-extending spring and the adjacent end of the trackway, the spacing of the second spring and the bar being such as to form a clamp for the plate when detached from the first spring.

3. A Tsquare for mat cutters comprising a plate portion, a trackway mounted thereon, and a two-piece head portion comprising a flat bar rigidly secured to an end of the plate portion and having its inner edge terminating in substantially the vertical plane of the adjacent end of the trackway, and a detachable plate having a cut-out portion intermediate its ends of suflicient dimensions to permit the plate to straddle the blade, a pressed-up portion intermediate the ends of the plate having a width approximating that of the blade, a leaf spring secured to the flat bar and located adjacent the adjacent end of the trackway and extending vertically of the plane of the bar, a second leaf spring secured to the bar and having a portion spaced slightly therefrom, the pressed-up portion of the plate adapted to be inserted between the first-mentioned spring and the adjacent end of the trackway or between the second spring and the bar to maintain the plate in either its right angular position with respect to a flat bar or in superposed relation to the bar, respectively.

4. A T-square for mat cutters comprising a blade portion, a trackway mounted thereon, a two-piece head portion comprising a flat bar rigidly secured to an end of the blade portion and a detachable plate portion, and spring means having one end adapted to cooperate with the adjacent end of the trackway to support the plate in right angular positions with respect to the flat bar and the other end adapted alternatively to urge the plate against the upper surface of the bar.

5. A T-square for mat cutters comprising a blade portion, a trackway mounted thereon, a two-piece head portion comprising a flat bar rigidly secured to an end of the blade portion and a detachable plate portion, and an elongated leaf spring anchored intermediate its ends to said bar and having one end adapted to cooperate with the adjacent end of the trackway to support the plate in right angular positions with respect to the flat bar and the other end adapted alternatively to urge the plate against the upper surface of the bar.

References Cited in the file of this patent UNITED STATES PATENTS 552,845 Lewis Jan. 7, 1896 858,791 Breul July 2, 1907 1,488,401 McCracken Mar. 25, 1924 1,624,590 Fleming Apr. 12, 1927 1,745,476 Cohn Feb. 4, 1930 2,058,091 Marsella Oct. 20, 1936 2,098,616 Cutting Nov. 9, 1937 2,130,135 Jones Sept. 13, 1938 2,370,470 Joss Feb. 27, 1945 

